1. Field of the Invention
This invention relates to pickup trucks, specifically to a pickup-truck cargo bed which is built by the truck manufacturer to be convertible--from a fully-open position for carrying cargo, to a partially-enclosed position providing a storage compartment like the trunk of a passenger car.
2. Description of Prior Art
Most pickup trucks are built with the driver's and passengers' seats so close to the rear wall of the cab that the trucks have very little storage space that is enclosed, secure and weather-resistant, like the trunk of a passenger car.
Some pickup trucks are built with their cabs extended rearward to provide such storage space; but this is a costly option which makes a truck longer and less maneuverable. Moreover, the storage space in the rear of an extended-cab pickup truck is visible from outside the truck, which makes it less secure; and accessible only from inside the cab, which makes it less convenient.
U.S. Pat. No. 4,917,430 to Lawrence discloses a design for an after-market conversion for an extended-cab pickup truck. This design provides a small, externally accessible storage space in the area of the cab behind the seats. However, this design further complicates an already expensive option, and still leaves the truck longer and less maneuverable.
Many kinds of after-market storage units have been devised which can be installed in the cargo bed of a pickup truck to provide an enclosed, secure, weather-resistant storage compartment.
The units shown in U.S. Pat. No. 4,288,011 to Grossman, U.S. Pat. No. 4,488,669 to Waters, U.S. Pat. No. 4,770,330 to Bonstead et al., and U.S. Pat. No. 4,967,944 to Waters are examples of one type of such unit, the "straddle-bed" box, which is typically attached on top of the forward section of a cargo bed's side walls. Straddle-bed boxes suffer from several disadvantages. They may impede the rearward vision of short drivers. Their secure installation generally requires modification of the cargo bed, which was not designed to accept them. They are neither structurally nor esthetically integrated into the design of the pickup truck. Above all, if the entire cargo bed is needed for cargo, they get in the way and must either be put up with, or removed. If they are removed and left behind, they may well be unavailable when needed.
U.S. Pat. No. 4,936,624 to West discloses a variation of a straddle-bed box in which two rather small tool receptacles are arranged so as to be moved up and down between access positions and secured positions by hydraulic lifts. West's design extends very little above the top of the pickup-truck bed, so it would not significantly impede the rearward vision of short drivers; but it suffers from all the other disadvantages mentioned above in the discussion of straddle-bed boxes. It is a specialized piece of after-market equipment which would be useful for some persons who must work with heavy tools, for example; but it would be expensive to build, it offers very little effective enclosed storage space, and its complexity tends to make it a system which would be more or less permanently installed, occupying a significant portion of the open cargo space in the cargo bed.
U.S. Pat. No. 4,580,827 to Feagan discloses an "apparatus for storage compartmentation in combination with" a straddle-bed box. This design does make possible an additional enclosed space underneath and behind the straddle-bed box, but it suffers from all the limitations of that type of storage unit.
U.S. Pat. No. 3,485,522 to Reinarts and U.S. Pat. No. 4,892,346 to Berlin disclose units similar to straddle-bed boxes, except that they are extended vertically to substantially the height of the pickup-truck cab. These units may serve as auxiliary cabs, but they are large and bulky, and they suffer from all the disadvantages of straddle-bed boxes.
U.S. Pat. No. 4,451,075 to Canfield, U.S. Pat. No. 4,506,870 to Penn, U.S. Pat. No. 4,749,226 to Heft, U.S. Pat. No. 4,828,312 to Kinkel et al., and U.S. Pat. No. 4,938,398 to Hallsen disclose various types of storage units designed to be installed in the rearmost section of a pickup truck's cargo bed. These units suffer from three serious disadvantages: first, their location all the way in the rear of the pickup truck subjects items stored in them to the most severe vibration experienced anywhere on the truck; second, heavy loads stored in them, being behind the truck's rear wheels, will tend to lift the truck's front wheels, with possible dangerous effects on the truck's handling; third, they make it impossible to slide objects into the cargo bed over the lowered tailgate. The Penn patent, moreover, is limited in its use to trucks having "substantially vertical side walls," i.e. with the rear fenders outboard of the side walls. Few pickup trucks these days are built that way.
U.S. Pat. No. 4,789,197 to Lewis and U.S. Pat. No. 4,946,217 to Steffens et al. relate to covers which can enclose the entire bed of a pickup truck. However, covers of this type must be opened if bulky cargo is to be carried, leaving no space in the cargo bed secure and weather-resistant.
U.S. Pat. No. 4,943,194 to Aguilar discloses an after-market "modularized system for enclosing selected portions of a pickup truck bed". As pictured, this system requires permanently attaching at least eight pieces of hardware to the truck bed. Selected portions of the bed are then enclosed by attaching three to seven additional assemblies to the permanently-attached items. No provision is shown for storing these additional assemblies aboard the truck.
U.S. Pat. No. 4,750,773 to Chapline et al. discloses a storage-box kit for installation in the forward section of a cargo bed. This design incorporates into the storage box the floor, left and right sides, and forward wall of the cargo bed. It adds a rear panel which when not in use folds down to lie on the bed's floor, and a lid which when not in use folds down against the bed's forward wall. The design would be very difficult to make weather-resistant. Moreover, when the rear panel is folded down onto the floor, objects being pushed forward along the floor would hit the edge of the rear panel, perhaps causing damage, or have to be lifted over the edge.
U.S. Pat. No. 5,169,200 to Pugh discloses another storage-box kit for installation in the forward section of a cargo bed. This design incorporates into the storage box the floor, left and right sides, and forward wall of the cargo bed. It adds a three-piece rear panel, a lid, and a number of other parts, some more or less permanently installed in the cargo bed, and some removable. The design would be very difficult to make weather-resistant, and its large number of pieces would be an inconvenience. Moreover, when its pieces are removed to allow the whole bed to be filled with cargo, they have no storage space provided aboard the truck, so they must be brought along in some improvised way, or left behind.
U.S. Pat. No. 5,201,561 to Brown discloses another storage-box kit for installation in the forward section of a cargo bed. It is less complicated than Pugh, and larger, but it suffers from similar disadvantages.
U.S. Pat. No. 5,188,414 to Burnham et al. discloses a pickup truck built at the factory with "an auxiliary load compartment . . . intermediate a load box and the conventional pick-up truck cab." This design would make a truck longer and less maneuverable, with its auxiliary load compartment permanently taking up a major part of the space that otherwise could be used for bulky cargo. Furthermore, the installation of a truck cap or similar enclosure over the entire cargo bed would make it impossible to open the doors of the auxiliary load compartment.